The present invention relates to a technique for displaying information concerning power consumption on a display in an electronic device driven by a battery, and more particularly to a technique for displaying information concerning power consumption with use of data received from an intelligent battery pack.
Lap-top personal computers (PC) are very convenient to use because they are provided with a rechargeable battery pack so they can be used anywhere commercial power supply is unavailable, away from homes and offices where they are usually used. On the other hand, the battery pack of such the lap-top PC can be charged by a commercial power source via an AC adapter connected to the power source after it is discharged by use away from the user""s home/office. If such a PC is driven by a rechargeable battery, it is desired first that the PC can operate as long as possible after it is charged once. In order to extend such a continuous battery driving time of the PC, therefore, there have been continued efforts to improve the battery, reduce the power consumption of each component in the PC, etc. In addition, there have also been adopted techniques for lowering the clock frequency of the CPU in accordance with the operation state of the PC, as well as stopping electric power supplied to the CPU and peripheral devices of the PC so as to be automatically shifted between the normal operation mode and the energy-saving mode.
While a PC is driven by a battery, the voltage of the battery can drop abruptly and sometimes processed data is lost or scheduled work is disabled. To avoid such troubles, therefore, various techniques are adopted so as to provide the user with data denoting the residual capacity of the battery. According to those techniques, a battery, an MPU, a memory, etc. are combined so as to compose a battery pack. The MPU detects such battery-related parameter values as the voltage, electric power, temperature, etc. of the battery being discharged. Then, the battery residual capacity is calculated according to those parameter values with reference to the data specific to the battery stored in the memory beforehand. In this specification, such a battery pack is referred to as an intelligent battery pack (hereafter, to be referred simply to as a battery pack or intelligent battery pack). The battery pack has a communication line connected to the subject system, so that the residual capacity calculated by the MPU and the parameter values detected by the MPU are sent to the system. The system then displays the residual capacity information of the battery received from the MPU on a display and uses other parameter values as information of the electric power managed by the OS.
Published Unexamined Patent Application No. 9-289742 discloses a technique for estimating a residual capacity of a battery accurately in an electronic device provided with a battery and an AC adapter as power sources. According to this technique, while the subject PC is driven by the AC adapter and the battery is charged so as to measure its voltage and know the residual capacity, charging of the battery by the AC adapter is stopped once, thereby the voltage of the battery is measured while no charging current flows in itself.
On the other hand, Published Unexamined Patent Application No. 10-187299 discloses a technique for notifying the user of a residual capacity of the subject battery accurately in a portable information device driven by a plurality of batteries that can communicate information including the voltage or residual capacity of each of those batteries. According to this technique, when the information concerning the residual capacity of the battery is obtained, the subject battery is put under an actual load once, then the residual capacity is measured, thereby calculating the residual capacity more accurately.
The power consumption of a PC is also changed by an executed application program. In order to extend the operation time of a PC driven by a battery, therefore, the user must think out a proper idea for running the object application program. It is one of the methods for solving the problem. According to this method, however, the user should always know the type of the object application program, as well as the relationship between the execution state and the power consumption of the PC. Of course, it should be avoided to execute application programs unnecessarily so as to reduce the power consumption even when the PC is driven by a commercial power source.
As disclosed in the above specification, the residual capacity of the conventional battery is displayed on a screen. The information provided to the user in this way, however, is not enough to reduce the power consumption of the PC and extend the battery driving time by selecting how to use the PC, that is, a proper execution method of each application program.
Operating systems (OS) such as Windows (Windows is a trademark of Microsoft Corp.) and OS/2 (OS/2 is a trademark of IBM Corp.) have a tool from the beginning. The tool notifies the user of the running state of the CPU decided by an execution method of the subject application program from the beginning. The tool is, for example, a performance meter (also referred to as a performance monitor, a system monitor, a system activity monitor, etc.). The tool counts the number of clocks of the CPU so as to notify the user of the running state of the CPU. For lap-top PCs, however, the actual operation state of the CPU cannot be notified correctly, since such lap-top PCs employ a power management method that stops the CPU clock respectively as needed. In addition, the performance meter does not provide the user with information related to the power consumption of the system and the tool is not enough for the user to think out a proper method for using the PC so as to reduce the power consumption.
Under such circumstances, it is an object of the present invention to provide an electronic device driven by a battery and enabled to display information of its power consumption on a display screen. It is another object of the present invention to provide an electronic device driven by an intelligent battery pack enabling the sending of information concerning power consumption and enabled to display information concurring power consumption obtained from the battery pack on a display screen. It is still another object of the present invention to provide an electronic device driven by an AC adapter or intelligent battery pack and enabled to display information concerning power consumption on a display screen even when it is driven by any of the above power sources. It is still another object of the present invention to provide an electronic device driven by an intelligent battery pack or AC adapter and enabled to display information concerning power consumption on a screen with use of a simple means.
An embodiment of the present invention is an electronic device provided with a display and driven by a battery. The electronic device comprises means for detecting information concerning power consumption of the electronic device and means for displaying the detected information concerning power consumption on the display screen. Such information concerning power consumption should preferably be obtained beforehand so as to extend the battery driving time as long as possible in the above electronic device driven by the battery. The display is effective as a user interface for visualizing information concerning power consumption, so the user can know the power consumption of the electronic device easily from the displayed information concerning power consumption.
The means for detecting information concerning power consumption may be any that can detect the state of electric power supply from any of the AC adapter and the battery. The battery may be any of chargeable and non-chargeable ones. The unit of information concerning power consumption may be any of an electric power, a current, and a substitute value related directly to those items. The substitute value may be, for example, a percentage rate of actual power consumption to the maximum power consumption.
Another embodiment of the present invention is an electronic device driven by a battery pack enabling the sending of information of its power consumption. The electronic device comprises a micro-controller for receiving information concerning power consumption from the battery pack and outputting the information of the power consumption and a display for displaying the information of the power consumption received from the micro-controller. In this embodiment, because the battery pack itself sends the information of its power consumption to the electronic device, there is no need to specially prepare a circuit for detecting information of such the power consumption. In addition, the micro-controller processes the information of the power consumption received from the battery pack and outputs the processed information of the power consumption, thereby a method for displaying the information can be employed appropriately to the use purpose.
Still another embodiment of the present invention is an electronic device driven by an AC adapter or battery pack enabling the sending of information of its power consumption. The electronic device is provided with a controllable switch for shutting off the electric power supplied from the AC adapter so as to select the power supply from the battery pack for a predetermined time when the AC adapter supplies an electric power to the electronic device; a micro-controller for outputting a control signal to the switch so as to shut off the power supply from the AC adapter and receive information concerning power consumption from the battery pack and outputs the information; and a display for displaying the information of the power consumption received from the micro-controller.
In this embodiment, it is possible to obtain information of the power consumption from the battery pack by setting the switch circuit so as to supply the electric power to the electronic device from the battery pack even when the electronic device is driven by the AC adapter. The electric power can thus be displayed when the electronic device is driven by the AC adapter.
According to the present invention therefore, it is possible to provide an electronic device driven by a battery and enabled to display information concerning power consumption on its display screen. It is also possible to provide an electronic device driven by an intelligent battery pack that can send information concerning power consumption and enabled to display information concerning power consumption received from the battery pack. It is still possible to provide an electronic device driven by an AC adapter or intelligent battery pack and enabled to display information concerning power consumption regardless of the power source (AC adapter and intelligent battery pack). And, it is still possible to provide an electronic device driven by an intelligent battery pack or AC adapter and enabled to display information concerning power consumption with use of a simple means.